The invention concerns piezoelectric resonators and generally electronic components comprising at least one such resonator.
The search for further improved manufacturing methods in order to permit mass production and resulting lowering of costs thereof has led to the conception of quartz resonators referred to as monolithic, that is to say such as described for instance in French patent applications FR No. 78 33349 and FR No. 78 33350, wherein the resonating element and its support are formed of and from a single piece of material. In such resonators the resonating element is cut out from a piezoelectric layer without being been detached therefrom: in the region of the non active zones the resonating element remains attached to the layer which thus forms a frame support. The resonant element is thereafter provided with electrodes by metal deposits, and in the same manner its frame receives metallized tracks intended for electrical connection of the electrodes with the exterior as well as final assembly by welding of covers on each of the faces of the frame, this resulting in a high quality package.
This technique has led to the possibility of mass production of resonant elements associated with supports having an excellent mechanical resistance. However such individual elements must thereafter be separated from one another in order to realise the packaging and thus the methods of mass production must then be replaced by individual treatment. Moreover it is to be noted that mass production processes have not, up to the present time, been applied except for simple units and never for more complex components which might for instance comprise several resonators and eventually further electronic components which might possibly be integrated therewith.
These limitations, and notably the fact that individual handling of the resonators for the operations of assembly and termination do not appear rational and are a source of time loss have led to efforts for developing new components utilising monolithic resonators to which may be applied manufacturing processes permitting mass production, even for the more complex components comprising several resonators and eventually further elements which may be integrated on the same layer from which the resonators are obtained, thus permitting the realisation of hybride circuits.